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Prof-x
21-07-2005, 13:58
They say the optimal MTU value for cable is 1500. Some adsl providers recommend lower values, i read an article that suggested some Nildram providers mentioned the optimal MTU was 1458 for their service.

Are there any benefits to using lower MTU values like this on cable? E.g. more reliable data transfer... this was one thing mentioned for adsl users.


TIA

Ignition
21-07-2005, 14:56
No, lower MTUs on ADSL are due to the different encapsulation used on UK DSL (PPPoA - Point to Point Protocol over ATM) and the tunneling used to deliver the cells to end providers, whereas cable modems use straight ethernet between modem and customer, so the optimal MTU is the same as for all other 10/100 Mbit ethernet networks, 1500.

AmAtoL
25-07-2005, 22:57
Sorry, I had to jump in this thread and ask a follow on question if you don't mind :)

I run my PC's through a Linksys BFSR41 router and was wondering if it is advisable to set the MTU value as above, at the moment it is disabled in the router. My 3mb connection comes from a Samsung STB which I am not totally happy with.

Thx

homealone
25-07-2005, 23:06
Sorry, I had to jump in this thread and ask a follow on question if you don't mind :)

I run my PC's through a Linksys BFSR41 router and was wondering if it is advisable to set the MTU value as above, at the moment it is disabled in the router. My 3mb connection comes from a Samsung STB which I am not totally happy with.

Thx

I run a 2MB connection through a befsr41 router, MTU is disabled, no problems, but mine is connected to a sacm, not a stb, I don't know if that would make a difference - have you checked you have the latest 'firmware' installed in your router?

Ignition
25-07-2005, 23:09
Default MTU on Windows is 1500.

AmAtoL
26-07-2005, 14:28
That's what I was kinda getting at homealone, does it indeed make a difference to have it enabled for a STB or should it be left disabled ?
To be fair I haven't had any issues with the router really, apart from this being the 3rd one I've had after the other 2 died :mad:
We just suffer from terrible lag sometimes in online games as others do, I am just trying to build up a picture of what could be the cause, or various little tweaks/settings that I could use.
It would seem that I am not alone in all this though, but I do think it is an NTL issue wether their network or STB, obviously I cant be any more specific, it's just a feeling.

I was on the original Cable trial up here in Stockport all those years ago and I don't ever remember it being as inconsistent as it is at the moment.

homealone
26-07-2005, 15:12
That's what I was kinda getting at homealone, does it indeed make a difference to have it enabled for a STB or should it be left disabled ?
To be fair I haven't had any issues with the router really, apart from this being the 3rd one I've had after the other 2 died :mad:
We just suffer from terrible lag sometimes in online games as others do, I am just trying to build up a picture of what could be the cause, or various little tweaks/settings that I could use.
It would seem that I am not alone in all this though, but I do think it is an NTL issue wether their network or STB, obviously I cant be any more specific, it's just a feeling.

I was on the original Cable trial up here in Stockport all those years ago and I don't ever remember it being as inconsistent as it is at the moment.

theoretically, as they are both used as network devices, there should be no difference. You may have more luck with your gaming if you try to throttle the upload, however I agree that there seem to be a number of people finding problems with gaming on the 3MB connection & I wonder if the big difference between upload & download speeds is a factor??

AmAtoL
26-07-2005, 21:27
Wouldn't throttling the upload give me other problems in a gameplay sense ?

When someone is downloading at the same time as someone gaming the problem becomes much more dramatic and playing is imossible.
I guess I'll just have to wait until the kids are in bed to be able to play in a half decent fashion :rolleyes:

KevAmiga
27-07-2005, 11:05
I run my PC's through a Linksys BFSR41 router

Same here, into an Ambit 200 SACM. I left the MTU setting alone, have never had any problems downloading huge files (Linux distro DVD's, apprx 3-4gb in size at full speed). On my network, i do find that if one PC is downloading, the others will experience a slowdown in the browsing, im guessing due to the low upload bandwidth you have ... possibly ? Im not much of a gamer sorry...

SMHarman
27-07-2005, 11:11
Upgrade your router to a BEFSR81 and use the QoS functoinality to prioritize gaming traffic over browsing / FTP traffic.

KevAmiga
27-07-2005, 11:14
Isnt there a firmware flash for the BEFSR41?

AmAtoL
27-07-2005, 21:26
Upgrade your router to a BEFSR81 and use the QoS functoinality to prioritize gaming traffic over browsing / FTP traffic.




An 8 port router is going to be a bit lost with so few connections :erm:


I take it that only the more expensive models have this function, I'll have to check it out. Sounds like a plan though with 3 of us gaming at a night time.......
As for the firmware flash I've tended to not bother as Linksys say only do it if you are having problems, I know it sounds a bit contradictory but I think the problem is more than that.

KevAmiga
28-07-2005, 08:27
True, i had a problem with mine and disconnections and a flash sorted that out.... just a suggestion.

SMHarman
28-07-2005, 11:26
An 8 port router is going to be a bit lost with so few connections :erm:

I take it that only the more expensive models have this function, I'll have to check it out. Sounds like a plan though with 3 of us gaming at a night time.......
It's not exactly much more expensive, especially as you could probably get a reasonable price for yours on ebay (or on the sale board here?)

Maybe it looks a little lonely with only 3 of 8 lights blinking, but it wouldn't be something I would worry about on it. Mine only has four pieces of hardware plugged into it and one of those is a hub because I didn't put enough ethernet sockets in one place!